Does anyone know where one can obtain the old fashioned HS steel guy wire?
When I worked at a broadcast station back in the 60's, I recall that you
had a choice of guy cable:
HS = Hardened Steel, AKA High Strength
EHS = Extruded Hardened Steel, AKA Extra High Strength
Whatever you choose to call it, EHS is a pain to work with. It can even be
dangerous. I almost lost an eye once when I bent a strand of EHS on a cold
day, and a piece about two inches long broke off in a sliver, with a
needle-sharp point. It hit me in the eye, but luckily the side of the wire
hit my eyeball, not the sharp end. It actually left a visible dent in the
cornea. I could imagine what would have happened if it had hit sharp end
first. The stuff is more difficult to work with than copperweld.
On the other hand, HS cable is softer and less springy. If you bend it, it
stays in the shape you bent it. It is very difficult to break a strand by
simply bending it; you have to repeatedly flex it back and forth until it
finally fatigues. All told, it is much easier to work with than EHS.
HS has only about 60% of the rated breaking strength of EHS, but if a tower
is subjected to enough wind to break a HS guy wire, the tower and
transmitter building probably wouldn't survive the storm regardless.
The only problem is that I can't find anybody who sells it. It used to be
listed in the Rohn catalogue circa 1964. You had a choice of HS or EHS, and
HS was substantially less costly.
I recall an AM broadcast station where over 100 guy wire insulators were
attached simply by serving the cables - no clamps or anything else. The NAB
Radio Engineers handbook says that serving is more secure than three cable
clamps without serving. A friend of mine who once worked for a utility
company in Germany said that the guy wires on their utility poles were
always attached simply by serving and nothing more.
It is impossible to properly serve a cable made of EHS. As soon as you wrap
the strands tightly, and remove the serving tool, they spring back and
partially unwind, leaving a very loose wrap. My near mishap occurred when I
was trying to serve strands of EHS following 3 cable clamps.
Of course, Big Grips are much easier and well worth the extra cost. But if
you could still get HS cable, there would be no need for clamps or
pre-forms.
Don k4kyv
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